One of the things I have noticed when I came to live here in Seoul more than five years ago was the unwritten escalator “etiquette” that Seoulites were accustomed to. If you are in a hurry and you want to walk up or down in the escalator you have to take the left side. If you want to take the leisurely escalator ride and remain stationery, you have to take the right side. Even couples do that.
Apparently, it’s not going to be anymore. It is being discouraged and advertisements are out educating escalator users not to walk up or down for safety reasons. When using the escalator, you have to be stationery as you are, in the first place, meant to be.